In general, a light emitting diode (hereinafter referred to as LED) is basically composed of a junction of a p-type and an n-type semiconductor. In addition, the LED is a kind of photoelectronic device that emits energy corresponding to a bandgap of a semiconductor in a form of light by the combination of electrons and holes as a voltage is applied.
This LED is widely used in a range of applications such as a high luminance light source for flash, a backlight for a liquid crystal display (LCD) used in a portable electronic product such as a mobile phone, a camcorder, a digital camera, and a PDA, a light source for a electronic signboard, a light source of switch illuminating and lighting, a light source of an indicator and traffic lights.
This LED is developed as a Surface Mount Device (SMD) type that is mounted using Surface Mount Technology (SMT) according to a trend of miniaturization, slimness or the like of an information communication device.
However, in the case of a printed circuit board on which an LED is mounted, a size of the printed circuit board is increased in consideration of a driving device necessary for driving the LED and the LED's own heat dissipation characteristic, which leads to a limitation in a module's own miniaturization. In addition, a structure of a heat sink for dissipating heat from a device having a large amount of heat such as an LED is essentially arranged, which causes a problem for the trend of miniaturization described above.